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Fixed antenna for CICO & CBET

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n8fnr
Posts: 87
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Fixed antenna for CICO & CBET

Post by n8fnr » Fri Dec 11, 2020 2:07 pm

I want to put up a fixed TV antenna at about 20 feet for CICO and CBET in Windsor. According to RabbitEars they are 27 miles from my house. Since CBET is high VHF (channel 9 actual channel) and CICO is channel 19 I will need a VHF/UHF antenna. I am trying to get a smaller antenna and wonder if the folks here think that this will be good enough for my needs; https://www.solidsignal.com/rca-high-vh ... nna-ant751. Sadly there is no gain mentioned. Or perhaps I need one that is a little bigger? Any suggestions?

Thanks
Zack S



CK-722
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Re: Fixed antenna for CICO & CBET

Post by CK-722 » Fri Dec 11, 2020 2:49 pm

As long as there aren't any hills, buildings, dense forests, or other terrain blocks in between, it should work fine. A neighbor of mine is using this same antenna to pick up VHF High signals 50 miles away. Don't know about a closer UHF because the terrain is shadowed for UHF.


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Same (x, y, z), different (t)

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jimh
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Re: Fixed antenna for CICO & CBET

Post by jimh » Sun Dec 13, 2020 10:49 am

Re getting CICO-32 on RF 19: I think your biggest problem will be adjacent channel WTVS on RF20.

The WTVS transmitter is located roughly north of 8-Mile and east of Coolidge. Their signal is 345 kW erp. And you are likely much closer to them than you are to CICO-32

CICO-32 on RF 19 is only 14.2 kW erp, and the path is longer.

The power difference is 24.3 or 13.9 dB.

I don't know your distance to WTVS, but let's assume it is 2.7-miles. The path to CICO-32 is ten ten times longer. A general assumption of path loss is that it varies with -20 log (d) or in this case 20-dB more path loss for CICO-32. And that is for a free space model. Over terrain the path loss will be even higher. Look up the estimated difference in signals in dBm at your location of RABBITEARS.INFO.

Now we can estimate the difference in signal strength at your location: -13.9 on erp and -20 on path distance, or about 33.9 dB difference in signal.

If the path to CICO-32 from your location also points at the WTVS antenna, any antenna gain will likely help both signals. In that case, your receiver will be getting a very strong signal on RF20. The receiver now has to pull CICO-32 out with a 33.9 dB weaker signal on the adjacent channel. The outcome is hard to predict.

If you happen to be located so that the paths to WTVS and to CICO-32 are not aligned, an antenna with a tight pattern for UHF might help by putting WTVS in a null in the pattern.

The same situation applies somewhat for CBET-9. WJBK TV2 is on RF 7. I used to receive CBET-9 using a very large VHF Hi-band yagi. Unfortunately, at that location the path to CBET was also almost pointed at WJBK on RF7, which was just 4-miles away. I had a notch filter in the transmission line from the yagi to knock out RF 7. Without that filter there was no trace of CBET-9 on my receiver.

The antenna you propose may work depending on your location and the difference in direction from your location to RF7 and RF20. It is only a $50 bet, so why not try it.

Another consideration: the antenna you mention is designed for a 300-Ohm feed. This requires a balun. The quality of the balun will be important. I prefer antennas with feedpoint impedance designed for 75-Ohm or ones with a balun assembly that encloses the balun.

de K8SS
Last edited by jimh on Sun Dec 13, 2020 1:44 pm, edited 2 times in total.



CK-722
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Re: Fixed antenna for CICO & CBET

Post by CK-722 » Sun Dec 13, 2020 11:10 am

I had the Allied Colorset 60 VHF UHF FM Antenna beginning in 1969. It's on the cover of this catalog if it will load properly.

https://worldradiohistory.com/Archive-C ... Spring.pdf

I had it on an Alliance T-45 Rotator, but if your VHF and UHF were from slightly different directions, you could loosen the nuts that connected the VHF and UHF sections and reorient the UHF section. That would have worked well for the neighbor I mentioned, if the terrain issue wasn't insurmountable.


Is THAT where they got the idea for the 486-SX?

Same (x, y, z), different (t)

Your bullet missed my trial balloon.

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jimh
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Re: Fixed antenna for CICO & CBET

Post by jimh » Sun Dec 13, 2020 11:13 am

The proposed antenna being sold under the RCA branding is discussed in detail in a thread at

https://forum.tvfool.com/showthread.php?t=16264

The thread also discusses some misleading practices in selling this antenna. The short version: there are two different antennas. The original is longer and works better and is the model 751. The newer and smaller version is model 7511. Caveat Emptor.

The shipping cartoon for the longer 751 is much larger than for the 7511. See

http://forum.tvfool.com/attachment.php? ... 1492886569



CK-722
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Re: Fixed antenna for CICO & CBET

Post by CK-722 » Sun Dec 13, 2020 12:56 pm

Here's another popular one. There were or are different models with widely varying price range. It seems like some have rotators, some don't, some have preamps, some don't, some have both. Decent product from what I have heard from neighbors, but caveat emptor is applicable here also. The advantage over many other models is that it DOES have a VHF High Element, but little to no free antenna gain over larger models. "Free" antenna gain is the antenna gain over a reference dipole, which doesn't add noise to the signal like all preamps do, just at different levels of signal to the preamp. Like a free lunch, there is no preamp that has zero noise added, it is a characteristic of semiconductors operating above absolute zero temperature, and is called thermal noise in Physics.

Image


Is THAT where they got the idea for the 486-SX?

Same (x, y, z), different (t)

Your bullet missed my trial balloon.

RTN Price. Not guaranteed. As of 12:30, 157.71 Down 0.22.

Artificial Intelligence is a Child that needs a Parent to guide it through.

CK-722
Posts: 1284
Joined: Sun Dec 16, 2018 3:53 pm

Re: Fixed antenna for CICO & CBET

Post by CK-722 » Sun Dec 13, 2020 1:09 pm

RCA 751E

Image

I never thought to ask her what the letter [E] stood for,
But I know for sure it wasn't EXCELLENT.

RCA 751R is the smaller size.

One thing about TV antennas, is the more it looks like older TV antennas, the better. The antenna and TV industry took advantage of the fact that almost all the largest market stations used UHF during the transition, and recommended the micro antennas to viewers as a selling point to people who didn't know any better.


Is THAT where they got the idea for the 486-SX?

Same (x, y, z), different (t)

Your bullet missed my trial balloon.

RTN Price. Not guaranteed. As of 12:30, 157.71 Down 0.22.

Artificial Intelligence is a Child that needs a Parent to guide it through.

jimh
Posts: 65
Joined: Thu Sep 22, 2011 12:02 am

Re: Fixed antenna for CICO & CBET

Post by jimh » Sun Dec 13, 2020 1:49 pm

The wrong picture is often used with advertising for the RCA antenna. Ask for the shipping box dimensions. The smaller antenna box has the wrong picture on the box. Read the thread I mentioned earlier and look at the photo of the two boxes.



jimh
Posts: 65
Joined: Thu Sep 22, 2011 12:02 am

Re: Fixed antenna for CICO & CBET

Post by jimh » Sun Dec 13, 2020 4:11 pm

Consider this antenna:

https://www.dennysantennaservice.net/ez-hd-antenna.html

It is made by Winegard in Iowa. The vendor is in Michigan. No Chinese junk or overseas e-trailers.

The antenna is well made and thoroughly tested.

If room permits, this larger antenna should be a sure bet to get the stations:

https://www.dennystvantennare.com/hd-st ... gital-hdtv



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MWmetalhead
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Re: Fixed antenna for CICO & CBET

Post by MWmetalhead » Sun Dec 13, 2020 10:15 pm

I want to put up a fixed TV antenna at about 20 feet for CICO and CBET in Windsor. According to RabbitEars they are 27 miles from my house. Since CBET is high VHF (channel 9 actual channel) and CICO is channel 19 I will need a VHF/UHF antenna. I am trying to get a smaller antenna and wonder if the folks here think that this will be good enough for my needs; https://www.solidsignal.com/rca-high-vh ... nna-ant751. Sadly there is no gain mentioned. Or perhaps I need one that is a little bigger? Any suggestions?

Thanks
Zack S
If you reside in Metro Detroit, "gain" by electrical amplification - if that's what you mean - is completely unnecessary, and if anything, would be a severe detriment to reception due to RF overload.

Depending on the variation in azimuth between McGregor, Ontario and, say, the Southfield / Oak Park towers from your house, a rotor may be useful. That way you could purchase a directional antenna model and rotate (if needed) to maximize reception from a certain direction.

If your antenna is going to be outdoors and you don't have problematic obstructions in the direction from which you receive reception, an omnidirectional antenna with both UHF and VHF elements will probably work OK, no rotor necessary. Cannot guarantee it, though.
One thing about TV antennas, is the more it looks like older TV antennas, the better.
I 100% agree with this statement.



CK-722
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Re: Fixed antenna for CICO & CBET

Post by CK-722 » Mon Dec 14, 2020 12:57 am

They actually did come up with antennas that were Log Periodic, V Shaped Log Periodic, and combined design Log Periodics with High VHF directors to increase the gain and improve the pattern, that were close to the performance of the "713" designs, and even single channel VHF Yagis. So sometimes you can still get a 2-13 VHF antenna as good as a 713 design or single channel Yagi for VHF High.


Is THAT where they got the idea for the 486-SX?

Same (x, y, z), different (t)

Your bullet missed my trial balloon.

RTN Price. Not guaranteed. As of 12:30, 157.71 Down 0.22.

Artificial Intelligence is a Child that needs a Parent to guide it through.

jimh
Posts: 65
Joined: Thu Sep 22, 2011 12:02 am

Re: Fixed antenna for CICO & CBET

Post by jimh » Mon Dec 14, 2020 5:16 pm

CK-722 wrote:
Mon Dec 14, 2020 12:57 am
They actually did come up with antennas that were Log Periodic, V Shaped Log Periodic, and combined design Log Periodics with High VHF directors to increase the gain and improve the pattern, that were close to the performance of the "713" designs...
I am not familiar with "they" or the specification "713'" designs." Please give some antecedent noun for "they" and some pointer to an explanation of "713" designs.
Last edited by jimh on Tue Dec 15, 2020 9:18 am, edited 1 time in total.



jimh
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Joined: Thu Sep 22, 2011 12:02 am

Re: Fixed antenna for CICO & CBET

Post by jimh » Mon Dec 14, 2020 5:24 pm

The notion of antenna gain is due to entirely PASSIVE action, not to any sort of electrical amplification.

All antenna gain occurs by distortion of the radiation pattern into a single main lobe in one particular direction at the expense of significant reduction of radiation in all other directions. When used for RECEIVING signals, the feature of an antenna with GAIN that has a very clean pattern or radiation of only one main lobe is very much a benefit.

The classic antenna without GAIN is a simple half-wave dipole antenna, which has a rather broad radiation pattern. Using such a no-gain antenna to receive television signals will generally be unsatisfactory because the antenna will receive many reflected or multi-path signals. The arrival of multiple signals from the same source that have traveled different length paths will generally cause problems with reception.

To avoid problems with multi path signals, an antenna with GAIN in preferred because a small main lobe is more or less intrinsic with gain. The best antennas are carefully engineered to have minimal side lobes and back lobes in their radiation pattern. These antennas will deliver better reception due to their pattern discrimination than lo-gain antennas with non-discriminating patterns.

On that basis, I disagree that antenna GAIN is of no use in receiving a TV signal. In many cases, antenna GAIN with its intrinsically small main lobe pattern will produce superior outcomes.
Last edited by jimh on Mon Dec 14, 2020 5:37 pm, edited 1 time in total.



jimh
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Re: Fixed antenna for CICO & CBET

Post by jimh » Mon Dec 14, 2020 5:30 pm

Although much advice has been offered about a specific antenna to investigate for use as a fixed position antenna to receive CBET-9 (RF9) and CICO-32 (RF19), I will offer another recommendation. Consider a somewhat longer antenna with likely more gain and tighter pattern, made by WINEGARD:

HD7694P Platinum HD Series Antenna
https://winegard.com/products/hdtv-digi ... es-hd7694p

You can often get this antenna for under $60. SOLIDSIGNALS has it for about $55. See

https://www.solidsignal.com/winegard-ou ... es-hd7694p
"Your Price: $54.99" on the DAILY DEAL today.

As a simple metric, antenna gain is proportional to boom length. The HD7694p has a boom length of 65-inches.



CK-722
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Re: Fixed antenna for CICO & CBET

Post by CK-722 » Mon Dec 14, 2020 6:24 pm

I don't know which comment you are referring to, but when I said "free" gain, I just meant it didn't cause thermal noise. I didn't mean the gain was useless. In fact, it's much MORE USEFUL than preamp gain. There are almost no really weak signals that can be pulled in with an added preamp, many more with a good directional receiving antenna. I guess there are some very low noise figure preamps available, but they may have other problems like static blowing out semiconductor junctions, and overload by strong signals.


Is THAT where they got the idea for the 486-SX?

Same (x, y, z), different (t)

Your bullet missed my trial balloon.

RTN Price. Not guaranteed. As of 12:30, 157.71 Down 0.22.

Artificial Intelligence is a Child that needs a Parent to guide it through.

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